Adsorbing the magnetic superhalogen MnCl3 to realize intriguing half-metallic and spin-gapless-semiconducting behavior in zigzag or armchair SiC nanoribbon.

Hui Li,Zengsong Zhang,Wei Chen,Guangtao Yu,Yanfeng Ma,Xuri Huang

doi:10.1039/c8ra01632a

Abstract

By means of first-principles computations, we first propose a new and effective strategy through adsorbing the magnetic superhalogen MnCl3 to modulate the electronic and magnetic properties of zigzag- and armchair-edged SiC nanoribbons (zSiCNR and aSiCNR, respectively). In view of its large intrinsic magnetic moment and strong electron-withdrawing ability, the adsorption of magnetic superhalogen MnCl3 can introduce magnetism in the substrate SiCNR, and simultaneously induce the electron transfer process from SiCNR to MnCl3, resulting in the evident increase of electrostatic potential in the ribbon plane, like applying an electric field. As a result, the magnetic degeneracy of pristine zSiCNR can be broken and a robust ferromagnetic half-metallicity or metallicity can be observed in the modified zSiCNR systems, while a robust ferromagnetic half-metallic or spin-gapless-semiconducting behavior can be obtained in the modified aSiCNR systems. Note that both the appealing half-metallicity and spin-gapless-semiconductor behavior are key features which hold promise for future spintronic applications. Moreover, all of these new superhalogen–SiC nanosystems can possess considerably high structural stabilities. These intriguing findings will be advantageous for promoting excellent SiC-based nanomaterials in the applications of spintronics and multifunctional nanodevices in the near future.

Highlights

The discovery of isolated graphene, an extended honeycomb network of sp2-hybridized carbon atoms, has totally refreshed our minds and opened the gate to low dimensional nanomaterials.[1,2] Owing to its reduced dimensions, graphene can possess many fascinating physical properties,[3,4,5] such as massless Dirac Fermion behavior,[3] high mobility,[4] and the largest strength measured so far.[5]
We have considered two types of SiC nanoribbon with different edge chiralities, namely zigzag SiCNR and armchair SiCNR, as illustrated in Fig. 1a and c
Different widths of zigzag SiCNR (zSiCNR) and armchair SiCNR (aSiCNR) can be denoted as Nz-zSiCNR and Na-aSiCNR, respectively, where Nz or Na is the number of parallel zigzag chains or dimer lines across the corresponding ribbon width (Fig. 1a and c)

Summary

Introduction

The discovery of isolated graphene, an extended honeycomb network of sp2-hybridized carbon atoms, has totally refreshed our minds and opened the gate to low dimensional nanomaterials.[1,2] Owing to its reduced dimensions, graphene can possess many fascinating physical properties,[3,4,5] such as massless Dirac Fermion behavior,[3] high mobility,[4] and the largest strength measured so far.[5]. SiCNR (aSiCNR) can exhibit nonmagnetic semiconducting behavior with a band gap of about 2.373 eV,[33,34] and such a large band gap is not advantageous for its application in functional nanodevices.[35,36] To conquer these bottlenecks, some approaches have been proposed to modulate the electronic and magnetic properties of zSiCNR and aSiCNR systems,[37,38,39,40,41,42,43] for example, hydrogenation,[37] applying an electric eld,[38,39] edge modi cation with functional groups/atoms,[40,41] and (non)covalent surface modi cation with an appropriate molecule/ polymer.[42,43]. Differing from previously reported approaches, in this work we propose a new and effective strategy through adsorbing a magnetic superhalogen to tune the electronic and magnetic properties of zigzag- and armchair-edged SiC nanoribbons.

Computational methods

The electronic and magnetic properties of pristine SiC nanoribbons

Conclusions

Conflicts of interest